0434382 - ÚFCH JH 2015 RIV GB eng J - Journal Article
Smith, D. - Chippendale, T. W. E. - Španěl, Patrik
Reactions of the selected ion flow tube mass spectrometry reagent ions H3O+ and NO+ with a series of volatile aldehydes of biogenic significance.
Rapid Communications in Mass Spectrometry. Roč. 28, č. 17 (2014), s. 1917-1928. ISSN 0951-4198. E-ISSN 1097-0231
R&D Projects: GA ČR GA13-28882S
Institutional support: RVO:61388955
Keywords : SOLID-PHASE MICROEXTRACTION * TRACE GAS-ANALYSIS * ON-FIBER-DERIVATIZATION
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 2.253, year: 2014

RATIONALE It has been shown that aldehydes are often present in biogenic media. For their analysis by selected ion flow tube mass spectrometry (SIFT-MS), the rate coefficients and the product ion distributions for the reactions of the analyte ions H3O+ and NO+ with volatile aldehydes in the presence of water vapour are required. METHODS The reactions of H3O+ and NO+ ions have been studied with a series of n-aldehydes ranging from acetaldehyde (designated as C2), through undecanal (C11) under the conditions used for SIFT-MS analyses (1 Torr He, 0.1 Torr air sample, 300 K) and over a range of sample gas absolute humidity from 1% to 7%. For comparison, the C5 pentanal isomer 3-methyl butanal, the unsaturated trans-2-pentenal and trans-2-octenal and the aromatic benzaldehyde were also included in the study. RESULTS The H3O+ reactions led to the formation of protonated molecules MH+ and their hydrates MH +(H2O)0,1,2,3, and (MH+-H 2O). The NO+ reactions resulted in the production of NO+M adduct ions and of [M-H]+ fragment ions. The percentages of the different product ions for each aldehyde are seen to be dependent on the air sample humidity. Kinetic modelling was used to quantitatively explain these observations and to obtain rate coefficients for the association reactions producing NO+M adduct ions. CONCLUSIONS This detailed study has provided the kinetics data, in particular the product ion distributions, for the reactions of a number of volatile aldehydes, which allows their analyses by SIFT-MS in humid air, including exhaled breath, food emanations and other biogenic media.
Permanent Link: http://hdl.handle.net/11104/0238445